O'Donnell's triumph — along with a victory in the New York gubernatorial primary by businessman Carl Paladino over former Rep. Rick Lazio — sent a strong signal that the tea party rebellion is roiling the GOP across the land and will influence the outcome of November's congressional and gubernatorial elections.

O'Donnell will face Democrat Chris Coons for the Delaware Senate seat held for 36 years by Vice President Joe Biden. Since Biden left last year, it's been filled by Ted Kaufman, his former chief of staff.

Joseph Pika, professor of political science at the University of Delaware, said O'Donnell's victory reflected "lots of anti-establishment feeling . . . some anti-Washington, anti-career politician rhetoric, lots of energy — the enthusiasm and excitement in this election was all on O’Donnell’s side."

The result was particularly stinging for state Republican Party leaders, who had pushed Castle as the best bet to beat the Democrat in November. With 99 percent of districts reporting, O'Donnell had 53.1 percent of the vote to Castle's 46.9 percent.

In New York, Lazio, a veteran congressman and strong favorite of GOP regulars, was seen as a strong favorite over Paladino, a self-financed insurgent who echoed tea party calls to oust incumbents of all parties.

With 50 percent of precincts reporting, Paladino was trouncing Lazio, 66 to 34 percent. He’ll face New York Attorney General Andrew Cuomo, who starts the race as a big favorite, in November.

New Hampshire's Republican U.S. Senate primary race remained too close to call early Wednesday morning.

Tea party favorite Ovide Lamontagne, former state Board of Education chairman, was trailing former state Attorney General Kelly Ayotte, who was endorsed by former Alaska Gov. Sarah Palin. With 85 percent of precincts reporting, Ayotte had 46,331 votes to Lamontagne's 45,352.

The New Hampshire candidates are vying to succeed Sen. Judd Gregg, R-N.H., who is retiring.

"I'm not sure voters go through a lot of political calculation in their heads. They see someone who looks like the other guys in Washington, and they say, 'we're tired of Washington-speak,''' said Andrew Smith, the director of the University of New Hampshire Survey Center.

The O'Donnell and Paladino upsets continued a trend that began this spring, when a tea party favorite upset incumbent Republican Sen. Robert Bennett in Utah, and moved on through the defeat of incumbent GOP Sen. Lisa Murkowski in Alaska last month. They also defeated GOP stalwarts in Nevada, Kentucky and Colorado, and forced Florida Gov. Charlie Crist to leave the Republican Party and seek election to the Senate as an independent.

O'Donnell's triumph, though, is the most striking yet, because Castle, 71, has been winning statewide elections in Delaware for 30 years, while O'Donnell, 41, was making her third Senate bid in four years. The first two times she lost badly.

While Castle raised about $3.2 million and had a seasoned political staff behind him, O'Donnell had few resources, and raised only $376,000.

However, O'Donnell got help from the California-based Tea Party Express, which vowed to spend at least $250,000 on TV and radio ads for her, ads that branded Castle as a liberal and a supporter of the Obama agenda. He voted for the Bush-sponsored bank-bailout bill and the cap-and-trade climate change bill, but opposed Obama's stimulus legislation.

Last year the liberal Americans for Democratic Action rated Castle the House Republican most sympathetic to their views. He was hardly a liberal, however: The American Conservative Union said he voted its view 56 percent of the time.

The mild-mannered Castle fought back hard, unleashing a negative ad last week informing voters of O'Donnell's income tax problems and unpaid college bills. The Internal Revenue Service placed a lien against O'Donnell earlier this year for unpaid taxes.

O'Donnell countered that the agency later admitted it had erred. An IRS spokesman said he couldn't discuss individual tax matters. Newspaper reports also said that O'Donnell had contested her alma mater over payment of college expenses.

She called Castle's allegations "hysterical" as she traveled through the small state, harnessing the anger at Washington and a perception among conservatives that Castle wasn't sensitive to their concerns.

O'Donnell supporters asked backers at rallies to contact 10 friends. They vowed to knock on doors and find people who rarely vote in such elections — turnout in Delaware GOP primaries is traditionally below 20 percent.

They were motivated largely by anger at Washington.

"What set me off was the stimulus bill," said Chris Shirey, a Laurel, Del., respiratory therapist who's the state's tea party coordinator. "I'd be for it if was much smaller," she said.

She found like-minded people with other complaints. They were angry at Castle's support of the 2008 bank bailout and of the Democrats' cap-and-trade legislation last year.

"Look at cap and trade, why do we need it? And we're spending all this money, for what?" asked William Van Ness, a Magnolia, Del., engineer.

Castle was one of eight House of Representatives Republicans to support the legislation.

Castle backers, with strong support from the Delaware Republican party, tried to highlight his conservative bona fides, such as his votes against the Democrats' health care plan and against the stimulus.

They also tried hard to paint O'Donnell as unfit for office. "She's not a legitimate candidate," said state GOP chairman Tom Ross.

In New Hampshire, the campaign was less bitter. Lamontagne is no stranger to state politics; he upset favored U.S. Rep. Bill Zeliff 14 years ago and won the GOP gubernatorial nomination, then lost the general election.

However, Ayotte, who had the backing of former Alaska Gov. Sarah Palin, holds one potential advantage that Castle lacks: Independents can vote in New Hampshire's GOP primary, and were expected to do so for her in big numbers.

Still, tea party backers, with a strong push from the influential conservative Manchester Union-Leader newspaper, rallied behind Lamontagne. He's not a government official, they figure, and he has no ties to Washington.

In other primaries Tuesday:

Former Maryland Gov. Robert Ehrlich beat investor Brian Murphy in the state's GOP primary for governor. Murphy was given little chance, even though he won former Palin's endorsement last month. Ehrlich now faces a rematch with Gov. Martin O'Malley, who defeated him in 2006.

TEA PARTY PRIMER

The tea party movement emerged shortly after President Barack Obama was inaugurated in January 2009. Its initial anger was directed at federal bailouts for troubled financial institutions.

Although the bailouts were sponsored first by the Bush administration and mainstream Republicans in Congress and are credited with preventing the collapse of the nation's financial system, many conservatives grew upset at the government's debt-financed spending and its expanded role in the economy.

Other events gave the tea party momentum, notably Obama's election and the $814 billion economic stimulus that he and congressional Democrats sponsored soon after taking power. Then came the bitter debate over overhauling the nation's health care system, the effort to limit global warming with a carbon-emissions control system, and the sweeping legislation to overhaul financial regulation.

To tea party sympathizers, the events all fit a pattern: Government was growing too big and intrusive, and running dangerously high levels of debt.

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